Printing telegraph apparatus



June 4, 1940.

PRINTING TELEGRAPH APPARATUS Filed Dec. 17, 1936 2 Sheets-Sheet 1INVENTO'R EDWIN W. F. HANKE ATToR Y E. w. F. HANKE 2,203,300

June 4, 1940. E. w. F. HANKE PRINTING TELEGRAPH APPARATUS Filed Dec. 17,1936 2 Sheets-Sheet 2 INVENTORI EDWIN w. F. HANKE FIG. 9

ATTOR Y Patented June 4, 1940 PATENT- OFFICE PRINTING TELEGRAPHAPPARATUS Edwin W. F. Hanke, Chicago, 111., assignor t TeletypeCorporation, Chicago, 111., a corporation of Delaware ApplicationDecember 17, 1936, SerialNo. 116,271

16 Claims.

This invention relates to printing telegraph apparatus, and particularlyto selector mechanisms therefor. 7

An object of the invention is to increase the number of selectivepossibilities in a selector without increasing the time required for theperformance of selections.

Another object .of the invention is to provide compound adjustment of apivotally mounted element of a selector mechanism.

The invention features various styles of detents for an element of aselector which is shiftable into either of two selective positions, andwhich may bounce considerably before settling into the selectivepositions.

It is well known that in the use of permutation code combinations-ofimpulses for signalling, each additional impulse in the combinationdoubles the selective possibilities. Thus a five-unit code affordsthirtytwo usable selective combinations, and a six-unit code affordssixty-four usable selective combinations. In selector mechanisms such asthose shown in Patent No. 1,745,633 granted February 4, 1930 to S.Morton et al., in Patent No. 1,917,308 granted July 11, 1933 to H. L.Krum, and in Patent No. 1,937,376 granted November 28, 1933 to W. J.Zenner, the selective possibilities may be increased by adding onecomplete set of those elements, including cam projections, selectorsword levers, T1evers, etc., under the control of which notchedpermutation code bars are set. Thus a five-unit selector may beconverted into a six-unit selector, a six-unit selector may be convertedinto a seven-unit selector, etc. i

It should be remembered, however, that a selector mechanism thusconverted requires an additional impulse in the signal combination tocontrol the operation of the additional selector elements. If, in addinga code impulse to increase the selective possibilities, the same' speedof operation in cycles or code combinations per unit of time is to bemaintained, in order that the transmission of characters shall not beslower, and in order that special driving mechanisms need not beemployed, the code impulses must be proportionally shortened, and theoperation of each chain of elements controlling a code bar must beaccelerated.

The present invention relates primarily to those features by means ofwhich the selective possibilities of a selector mechanism are increased,while maintaining a given standard of operating efiiciency, includingthe modification oi the sword operating levers in a sword and T-leverselector and thediminution of bounce in the selector lever by means ofdetents. The invention also contemplates a compound adjustment of thepivotal mounting of the selector lever.

For a full and complete description of the invention, reference may behad to the following detailed description, taken in connection wit theaccompanying drawings in which Fig. 1 is a top plan view of one form ofselector mechanism having applied thereto one form of selector leverdetent;

Fig. 2 is a vertical sectional view taken approximately on the line 2-2of Fig. 1;

Fig. '3 is a view partly in section showing a sword lever operating bellcrank in relation to its associated cam projection;

Fig. 4 is a plan view having a portion broken away and showing anotherform. of selector mechanism which includes selector lever pivotadjusting means and another form of detent;

Fig. 5 is a perspective view of a portion of the selector mechanismshown in Fig. 4.;

Fig. 6 is a vertical sectional view taken ap proximately on the line 6-6of Fig. 4;

Fig. 7 is a detail view partly in section showing the mounting of thedetent shown. in Figs. 4 and 5; 1

Fig. 8 is a fragmentary view showing still another form of detent; I

Fig. 9 is a detail View partly in section showing the mounting of thedetent shown in Fig. 8; and

Fig. 10 is a fragmentary perspective view showing a modified selectorlever bracket adjusting system.

Referring now to the drawings, in which identical reference charactersdesignate corresponding parts throughout the several views, andparticularly to Fig. 1, reference numeral I6 designates a mounting platefor the several elements constituting a selector mechanism intended,primarily, ;for printing telegraph apparatus. A bracket llsecured toplate it by means of bolts l8 supports laminated core [9 of selectormagnet 2| which includes po-le face 22. Mounting plate 16 also supportsbracket 23 which has a pivotal mounting 24 for selector lever 26 whichhas rigidly secured thereto selector magnet armature 21. Tension spring28 has one end secured to armature 21 and the other end engaging tensionadjusting screw 29, whereby armature 21 and selector lever 26 are biasedto their extreme clockwise position, in which position armature 21'is inits retracted position corresponding to the deenergized condition of theselector magnet.

-At its outer or free end, selector lever 26 is provided with spaceddepending arms 3| (Fig. 2) Depending arms 3| are arranged to control thesetting of the thin, flat, selector levers contained in a sword andT-lever selector mechanism designated generally by the reference numeral32. Selector mechanism 32 includes a plurality of separator plates 33secured one above the other in spaced relation upon a plurality of studs34 carried by mounting plate l6. Between each two of the separatorplates 33 there is disposed a thin, flat, selector finger or sword lever36 arranged to undergo pivotal and reciprocatory movement. At itsleft-hand end, as viewed in Fig. 1, each of the sword levers 36 isprovided with a disc-like portion 31 which is retained in acorrespondingly shaped aperture in a thin, flat, bell crank lever 38pivotally mounted on pivot pin 39 and urged in clockwise direction bytension spring 4| connected to spring post 42. At its outer or righthandend, as viewed in Fig. 1, each sword lever 36 is pointed and abuts oneof a plurality of T- levers 43 pivotally mounted on pivot pin 44 andhaving outwardly extending arms 46 terminating in disc-like portionsthrough which T-levers 423 are adapted to be articulated to code discsor code bars not shown. Adjacent to its disc-like portion 37 each of thesword levers 36 is provided with oppositely extending arms 98 whichtermihate in abutments 49. The abutments 49 are spaced apart a distanceslightly greater than the distance between the depending arms 3| ofselector lever 26 so that when lever 26 is in its extreme clockwiseposition, which it occupies when selector magnet 2| is deenergized, oneof its arms 3| is in alignment with one set of abutments 49 of swordlevers 36, and when the selector lever 26 is in its extremecounterclockwise position, its other depending arm 3| is in alignmentwith the other set of abutments 49.

As shown in Fig. 2, a power-driven shaft extends through an aperture inmounting plate i6 and has secured thereto spaced discs 52 and 53. Aboveand below discs 52 and 53 respectively are friction discs 54 ofresilient material which frictionally engage end discs 56 rigidlysecured to a selector cam assembly 51. Cam assembly 5'! includes camprojections 58 equal in number to the number of impulses of a codecombination on which the selector mechanism is adapted to be operated,and, therefore, equal in number to the T-levers 43. The cam projections58 are arranged helically around the cam. assembly 51 and each camprojection is aligned with one of the bell crank levers 38. Cam assembly51 includes a cam 59 with which there is aligned the follower portion 6|of a selector lever locking bell crank 62 which is pivotally mountedupon pivot pin 39 and is urged in counterclockwise direction to bringits follower portion 6| into engagement with cam 59 by tension spring63. Looking bell crank 62 terminates in a locking projection 65 whichoccupies blocking position with respect to an abutment 64 of a selectorlever 26 when follower portion 6| rests against one of the nadirportions of cam 59.

Cam assembly 5'! includes a stop arm 66 which has at its outer endupstanding arm 61. Above cam assembly 61 there is fixedly mounted onposts 66, carried by mounting plate I6, a plate (I which carriespivotally mounted thereon coaxially with the shaft 5| a plate 12 onwhich is pivotally mounted a stop gate 13 which has a portion disposedin the path of upstanding arm 6! of cam assembly stop arm. 66. A stopgate latching lever M has a shoulder portion capable of locking stopgate I3 in position to arrest stop arm 66, and a compression spring 16urges 'lever '14 into engagement with stop gate 13. A bell crank leverTl pivotally mounted on bracket 18 carried by the rigidly mounted plate1| has one arm in operative engagement with looking lever 14 at a pointcoaxial with the pivotal mounting of plate 12 and with shaft 5|. Theother arm of bell crank 11 is aligned with a plunger pin 19 with whichthere cooperates an abutment screw 8| carried by arm. 82 rigidlyconnected to selector lever 25 and armature 21. The shank of screw 8| iseccentric with respect to the head thereof so that operativerelationship between arm 82 rigid with selector lever 26 and plunger pin19 may be adjusted as desired.

Plate 12 is mounted below plate 1| as indicated in Fig. 2. There is anarm 83 pivoted on plate 1| above said plate and coaxially with pivotedplate '12, and knurled locking screw 84 passes through arm 83 andthreadedly engages plate 72, whereby the latter plate may be clamped inany desired position with respect to fixed plate H.

Referring again to Fig. 1, it will be noted that selector lever 26carries an upstanding abutment pin 86 which in the particular embodimentis cylindrical. An arm 8'! pivotally mounted at 88 to bracket 89 has atits outer end a disc-like portion 9| which is held in engagement withabutment pin 86 by tension spring '92'which has one end engaging arm 81and the other end engaging bracket 69. Pivotally mounted arm 81 servesas a detent to reduce bounce in the operation of selector lever 26 aswill be described hereinafter. In operation, shaft 6| is continuouslyrotated and a continuous torque is applied to cam assembly 51 throughfriction discs 54. The selec tor magnet 2| is connected with a telegraphline and in a start-stop system of operation the line has currentflowing therein when the circuit is idle but conditioned for thetransmission of a message, whereby selector magnet 2| is energized andarmature 21 is attracted to pole face 22 as indicated in Fig. 1. Withthe armature at tracted, selector lever 26 is in its extremecounterclockwise position and plunger pin 79 is in its retractedposition, whereby the shoulder of lever 14 is permitted to engage thestop gate 13, which, in turn, restrains the cam assembly 5! fromrotating. The first impulse of any code combination which is applied tothe telegraph line is the start impulse, which is usually represented bya no-current condition on the telegraph line. The start pulse thusresults in the deenergiza tion of selector magnet 2| and permitsarmature 21 to be retracted by spring 28, whereby selector lever 26 isshifted to its extreme clockwise position, causing plunger 19 to bedepressed. Bell crank lever 71 is thus rocked counterclockwise (asviewed in Fig. 2), and lever I6 is rocked clockwise to lift its shoulderout of engagement with stop gate 13. The stop gate thus being permittedto rock, cam assembly 5'! responds to the torque applied by shaft 5| andescapes by rocking stop gate 13.

As cam assembly 51 rotates, cam 59 withdraws locking bell crank 62 fromlooking engagement with abutment 64 in timed relation to the signalimpulses applied to selector magnet 2|, whereby armature 21 is permittedto respond to conditions of energization and deenergization of magnet 2|and selector lever 26 is shifted into its clockwise or counterclockwiseposition in accordance with the signal impulses. Cam projections 58 rockthe-sword lever bell cranks 38 counterclockwise successively and intimed relation to the signal impulses so that sword levers 36 are drawnleftwardly (as viewedin Fig. 1). As each sword lever is thus movedleftwardly, one or the other of its abutments 49 is brought intoengagement with one or the other of arms 3| of selector lever 26, andthose sword levers which encounter one of the arms 3i before they reachthe limitof their leftward travel are rocked clockwise orcounterclockwise, depending upon the position in which selector lever 26is presented. Thus, the sword levers are set in permutative arrangementin accordance with signal impulses applied to the selector magnet, andsince each sword lever controls one of the T-levers 43, and mayencounter the T-lever on either side of its pivot 44, the T-levers areset in permutative arrangement corresponding to the sword levers 36 andin turn position the code discs or code bars to which they arearticulated.

The final impulse in a signal combination is a stop pulse, which isordinarily represented by current on the telegraph line and so resultsin energization of selector magnet 2| and attraction of its armature 22.Plunger pin 19 is thus permitted to move to its retracted position andlever 14 is presented in looking engagement with stop gate 13, theseconditions being effected by compression spring 15. Stop gate '13 thusbeing locked arrests stop arm 66 and cam assembly 5! at the conclusionof one revolution and the selector magnet is thus conditioned forreception of the next code signal combination. In such stop condition,the locking bell crank lever 62 engages a high portion of cam 59 and isthus held out of blocking engagement with abutment 64 so that selectorlever 26 is capable of responding to a start pulse applied to theselector magnet.

As previously set forth, it is desirable not to reduce the operatingspeed of a selector mechanism and associated printing telegraphapparatus when such selector mechanism is converted to increase theselective possibilities, as from fiveunit to six-unit code operation. Itis desirable to maintain standard operating speed in order that theefiiciency of thetelegraph line shall not be diminished and also inorder that standard driving mechanism may be employed. Thus, it will bedesirable to operate shaft 5| at the same velocity regardless of whetherthe selector mechanism is to position live or six code bars or discs,but if a five-unit code is employed, five sword levers will be setpermutatively during one revolution of cam assembly 51, whereas, if asix-unit code is employed, six sword levers36 will need to beconditioned permutatively in the same time interval. Under suchcircumstances, the interval of time in which the selector lever 26 maybe set and the bell crank lever 38 rocked counterclockwise to draw swordlever 36 leftwardly, will be shorter in six-unit code operation than infiveunit. code operation; One of the methods by which the time intervalfor one sword lever operating cycle may be reduced is to accelerate thethe point at which cam projection 58 engages lever 38 and that as thecurvature of lever: 38 at the point of engagement is altered and mademore concave, as indicated in dotted lines in Fig. 3, cam projection 58willengage lever 38 later thanit would with the curve as indicated insolid lines and will be in engagement with lever 38 for a shorter periodof time so that bell crank 38 will be moved to its counterclockwiseposition more rapidly and therefore the setting of the associated swordlever will be consummated in a shorter period of time.

. It is essential that the selector lever 26 be brought substantiallyinto rest position and locked in that position by the locking bell cranklever 62 before an abutment 49 of one of the sword levers 35 is broughtinto engagement with one of the arms 3| of selector lever 26 byoperation of the associated bell crank lever 38. Accordingly, it hasbeen found desirable to bring about some of the reduction in theoperating cycle of a sword lever in the setting of the selector lever 26rather than to attempt to accomplish all of such reduction in theoperation of the sword lever operating bell crank 38.

The response of armature 21 to energized condition of selector magnet 2|is relatively violent and thus selector lever 26 may vibrate or bouncebefore coming to rest in its extreme counterclockwise position.Similarly, spring 28 is relatively violent in the rocking of selectorlever 26 clockwise and the lever tends to vibrate before coming to restin its extreme clockwise position. Locking bell crank 62 cannot bebrought into blocking relation with abutment 64 until the vibration ofselector lever 26 has been reduced to very small amplitude and a swordlever 36 cannot be moved leftwardly until selector lever 26 has beenlocked. More immediate locking of the selector lever in each sword leveroperating cycle is thus dependent upon reduction ofbounce of theselector'lever and this may be accomplished by means of the previouslydescribed detent lever 8! cooperating with upstanding abutment pin 86.As selector lever 26-passes from one of its extreme positions to theother, abutment pin 86 moves across the surface of disc-like portion 9|and rocks detent lever 81 clockwise against the tension of spring 92.When detent lever 81 reaches its extreme clockwiseposition, abutment pin86 passes over the outermost portion of disc 9| and engages a descendingarc, whereupon spring 92 adds its eiiect to the force which is movingselector lever 26 to bring that lever into rest position, and little orno bounce occurs due to the detent action of lever arm '81. With thisarrangement the selector lever 28 may be blocked by locking bell crank62 much earlier in a sword lever operating cycle than is possiblewithout the detent lever.

The cylindrical abutment pin 86 and cooperating disc-like portion Sil ofdetent arm 81 were found to be particularly effective in the type ofselector mechanism shown in Figs. 1 and 2. The cooperating surfaces ofthe two elements have constantly changing slopes and the change is suchthat the force required to be exerted by the selector lever to rotatethe detent lever 81 against the tension of spring 32 is a maximum asselector lever 28 begins to move and decreases until it comes'to zerowhen the detent has been brought to its extreme clockwise position.Thereafter detent 8T exerts a continuously increasing force upon aselector lever to bring it to rest in the selective position.

The anti-bounce detent, disclosed in Figs. 1 and 2, is a permissivedetent in that it does not positively stop selector lever 26 in eitherof its extreme positions. Selector magnet 2| exerts a force uponarmature 2i tending to move the armature into engagement with pole face22, and

if any positive stop is employed near the free end of selector lever 25,that lever may become twisted or otherwise deformed, or even broken dueto the arrestment of the selector lever before armature 21 has come torest. Accordingly, it is desirable to apply any limiting stops which maybe employed to armature 21 and provide no positive stops to selectorlever 26. Looking bell crank 62 is not to be considered as a positivestop because it does not come into blocking relation with selector lever26 until after that lever has been brought substantially to rest.

Referring now to Figs. 4 and 5, there is shown a modified form ofselector mechanism similar to that shown in the hereinbefore mentionedZenner patent in which the selector lever is controlled in accordancewith the attraction or nonattraction of the selector magnet armaturewith out being connected directly to the armature. In Figs. 4 and 5,reference numeral IOI designates a mounting plate upon which ispivotally mounted bracket I02 which supports core member I03 of selectormagnet I04. Bracket I02 is pivotally mounted on plate IOI by means ofpivot screw I05 and its alignment with respect to plate I III isadjustable by rotation of screw I 06, which, having spaced head andflange between which stud I01 carried by plate I M is disposed, isincapable of axial movement and therefore imparts movement to bracketI02 which it threadedly engages. Clamping screws I00 extend througharcuate slots in bracket I02 and threadedly engage mounting plate I0 I,whereby bracket I02 may be rigidly clamped in desired position tomounting plate IN.

A bell crank lever, which comprises arms III and H2, and which iscommonly identified as an armature lever, is pivotally supported byscrew I05 and by coaxially mounted pivot screw H3 carried by bracketI02. Armature H4 of selector magnet I04 is rigidly secured to arm II?!of the armature lever. The free end of lever arm I II terminates in acam follower portion H6 which is adapted to engage an armature cam (notshown).

Mounting plate IOI supports a sword lever and T-lever assembly I I 8similar to assembly 32 of Fig. 1, and similarly including sword leversII 9 and T-levers I 2|. The sword levers H0 are provided with abutmentsI22 for cooperation with spaced depending arms I23 of a selector leverI24. Selector lever I24 is pivotally mounted by means of pivot screwsI26 on a bracket I21, which is adjustably secured to mounting plate MIin a manner which will be described hereinafter. Selector lever I24 hasconnected to it one end of a tension spring I28, the other end of whichis connected to extension I29 of arm III of the armature lever. Anabutment screw I3I also carried by extension I29 has its head inengagement with selector lever I24 to maintain spring I28 under tensionand to serve as a positive drive between the armature lever and theselector lever in one direction. A locking lug I32 carried by selectorlever I24 at the free end thereof cooperates with a locking blade I33 oflocking bell crank lever I34 pivotally mounted on the pivot pin I36 tolock the selector lever in either of its two selective positions.Locking bell crank lever I34 is actuated to unlock and relock selectorlever I24 in timed relation to signals applied to selector magnet I04similarly to previously described locking bell crank 62, by a camsimilar to cam 50. A plate I31 similar to plate 1| carries a stop gate(not shown) for the arrestment of a selector cam assembly (not shown)and the stop gate mechanism includes a plunger pin I38 similar toplunger pin 19- which is controlled by an abutment screw I30 carried byextension I29 of flutter lever arm III. Clamping arm MI and clamp ingscrew I42 are provided for clamping the stop gate in any desiredposition of adjustability with respect to plate I31.

The previously described bracket I21, which pivotally mounts selectorlever I24, is provided with clearance holes I46 through which extendclamping screws I41 threadedly engaging mounting plate WI, and by meansof which bracket I21 may be clamped in desired position. Inter.- mediatethe clearance holes I41, bracket I21 is provided with elongated slot I48in which is diswhich has its center on the axis of adjusting screw headI5I, by rotating adjusting screw head I49 in slot I48. The eifect ofthis adjustment is to vary the distance between depending arms I23 ofthe selector lever and abutments I22 of sword levers II9. The pivotalmounting of lever I24 may be adjusted in a transverse direction byrotating screw head I5I which causes mounting bracket I21 to shiftlongitudinally while being guided by adjusting screw head I49 withinslot I48.

An anti-bounce detent lever I56 is adjustably mounted upon eccentricbushing I51 (Fig. '7) carried by post I58 which is supported by mountingplate II. A clamping screw I59 olamps bushing I51 in any desiredposition of adjustment while permitting detent lever I56 to rotatethereon. Detent lever arm I56 is provided'near its free end with an openaperture I6I, at the base of which is a crown or ridge I62 from whichoppositely sloping surfaces extend and intersect the sides. An abutmentpin I63 is mounted on the selector lever I24 and is disposed within theaperture I6I in detent lever I 56. A tension spring I64 biases detentarm I 56 in clockwise direction to bring the base of its aperture intoengagement with abutment pin I63.

'It will be noted that in the selector mechanism shown in Fig. 4, thearmature lever may be rotated into its extreme counterclockwise positionso that armature II4 engages the pole face of selector magnet I04without selector lever I24 being simultaneously correspondinglypositioned, and that the selector lever will become correspondinglypositioned when permitted to move by withdrawal of locking blade I33from blocking alignment with locking lug I32. It will also be observedthat when selector lever I24 is in its extreme counterclockwise positionand the armature lever attempts to rotate to its extreme clockwiseposition, it will be prevented from rotating due to engagement ofabutment screw I3I with selector lever I 24, until locking blade I33unlocks the selector lever.

The first impulse of a. signal combination is, as previously described,a start impulse, which results in deenergization of selector magnet I04,

whereupon armature I I4, being no longer held,

may be'drawn away from the pole face bythe armature lever which rotatesto its extreme clockwise position. Plunger pin I38 is thus depressed torelease the stop gate (not shown) to permit rotation of the selector camassembly (not shown). As the selector cam assembly rotates, itcyclically rotates. the armature lever to bring armature l M intoengagement with its pole face, it cyclically unlocks selector lever I24and it successively actuates the several sword lever operating bellcranks. When the armature H4 is held by magnet I04, after being rockedinto engagement with its pole face, abutment screw I3I is drawn awayfrom selector lever I24, and when looking bell crank I34 unlocks theselector lever, it rotates into its extreme counterclockwise position.When the selector magnet I84 is deenergized, armature H4 is not held andthe armature lever returns, or tends to return to its extreme clockwiseposition, where-upon the selector lever, if then in its extremecounterclockwise position, moves to its extreme clockwise position whenunlocked by the locking lever I34. In this manner the selector lever ispositioned selectively and sword levers I I9 and T-levers I2 I, arepositioned permutatively in accordance with signal impulses applied toselector magnet I84. Since the selector lever is not directly connectedto the selector magnet armature II4, it may lag behind the armature inits operation, under the control of the lock lever I34. Theinterconnection between armature H4 and selector lever I24 beingnon-rigid, as distinguished from the structure shown in Fig. l, thedetent arm IBI may include positive stops since there is no possibilityof injury to the selector lever as a result of violent operation of thearmature lever or selector magnet armature. Accordingly, the aperture inthe detent lever I56, in which abutment pin I63 is disposed, affords thepositive. stops comprising its opposite sides, and also affords thecamming surfaces comprising the oppositely sloping surfaces intersectingin the central ridge I62. When the selector lever I24 shifts from one toanother of its rest positions, the abutment pin I63 cams detent arm I56to rotate in clockwise direction in opposition .to tension spring I64until'ridge I62 is passed, whereupon spring I84 assists in bringing theselector lever into its rest position, and any tendency of the selectorlever to bounce is quickly eliminated.

In Figs. 8 and 9, there is shown another form of detent which may beemployed for reducing bounce in selector levers of the type shown inFig. 4, which are not rigidly connected to the selector magnet armature.This detent is designated by the reference numeral HI, and may be.mounted on the eccentric bushing I51 supported by post I58, as shown inFig. 9. Clamping screw I59 maintains bushing I51 in the desired fixedposition with respect to post I58 after it has been adjusted. Detentlever I1I is provided with a closed aperture of arcuate shape which isentered by detent pin I13 carried by selector lever I24. A tensionspring I14 urges detent I1I in counterclockwise direction, wherebydetent pin I13 is vcammed into abutment with one or the other of theends of arcuate aperture I12.

In operation, detent 'arm H1 is rotated clockwise as selector lever I24shifts fromone of its positions to the other and the tension in springI14 is increased during such rotation.

it adds to the restoring effect of spring I14 an As pin' I13 passes themidpoint of arcuate aperture I12,

additional driving force by engaging the righthand wall of aperture I12,as viewed in Fig. 8, and thus positively drives detent arm I1I into suchposition that pin I13 may come to rest at the end of the arcuateaperture. Any substantial tendency of selector lever I24 tobounce isresisted by the left-hand cam surface of the armate aperture I12 indetent arm I1I.

It will be noted that detent I'lI embodies positive stops for selectorlever I24 as in the case of detent I58 shown in Figs. i, 5, and 1.Detent I1I has the additional characteristic of aiding its restorationspring in returning it to normal position, which characteristic detentI56 does not possess due to the fact that the aperture therein is openat one side.

Detent I1I is shown as positioned below selector lever I24 with pin I13extending downwardly from the selector lever. It will be understood thatthis detent is capable of being mounted above the selector lever tocooperate withv a detent pin upstanding therefrom, and that detent I56could, with equal facility, be positioned below the selector lever, ifdesired.

In Fig. there is shown a modified arrangement for adjusting the bracketwhich pivotally supports the selector lever in a selector mechanism ofthe type shown in Fig. 4. The principal difference between the adjustingarrangements is that in the structure shown in Fig. 10, the means bywhich the selector lever is shifted longitudinally is not a permanentpart of the selector mechanism. It will be noted, in Fig. 10, that themounting plate IllI supports a selector lever bracket I8I which hasclearance holes :82 through which extend the shanks I83 of clampingscrews similar to clamping screws I41 of Figs. 4: and 6 andsimilarthreadedly engaging mounting plate IIlI. Bracket ISI is pivotallymounted on the cylindrical head of screw I84 which may be an eccentricadjusting screw similar to screw I5I (Figs. 4, 5, and 6) On oppositesides of bracket I8I, mounting plate IflI is provided with cylindricalapertures I86. For adjusting bracket I8I angularly about mounting screwI84, there is provided a tool, the shank I81 of which is provided withan eccentric projection I88 of lesser diameter than shank I81 anddimensioned to enter freely either of the apertures I86 in mountingplate IIII. Eccentric projection I88 is adapted toenter one of theapertures I86, after which shank I81 may be rotated. I Projection I88will then define the center of rotation, and shank I81 constitutes aneccentric which, coming into engagement with bracket I8I, and therotation being continued, will shift bracket I8I angularly about thehead of screw I84. The direction of movement of bracket I8I isdetermined by the particular one of apertures I86 into which theeccentric tool is fitted. With this arrangement, the positioning ofbracket I8I may be accurately controlled, after which the bracket may bepositively retained in the desired position by means of theclampingscrews which extend through the clearance apertures I83.

Although specific embodiments of the invention have been shown herein,it will be understood that the invention is capable of modification,rearrangement, and substitution within the scope of the appended claims.

vWhat is claimed is:

1. In a selector mechanism, signalresponsive means, a selector elementpresentable in either of twoYpositions under control of said means,

means for operatively supporting'said selector element, means forimparting movement of one character to said supporting means, and meansfor imparting movement of another character to said supporting means.

2. In a selector mechanism, signal responsive means, a selector elementpresentable in either of two positions under control of said means,means for operatively supporting said selector element, means forimparting compound movement to said supporting means, and means forclamping said supporting means to resist such movement.

3. In a selector mechanism, signal responsive means, a selector elementmovable to either of two selective positions under control of saidmeans, means for pivotally supporting said selector element having acircular aperture and an elongated aperture therein, and meanscomprising eccentrics disposed within said apertures for impartingcompound movement to said supporting means,

4. In a selector mechanism, signal responsive means, a selector elementpresentable in either of two selective positions under control of saidmeans, means for pivotally supporting said selector element having acircular aperture and an elongated aperture therein, and eccentric meansdisposed within said apertures for shifting the pivotal axis of saidselector element longitudinally and transversely of said element.

5. In a selector mechanism, signal responsive means, a selector elementpresentable in either of two selective positions under'control of saidmeans, a bracket having pivotal means for supporting said-element, saidbracket'having a circular aperture and an oblong aperture therein, arotational member having an eccentric portion disposed within saidcircular aperture in substantially close-fitting relation therewith, anda rotational member having an eccentric portion disposed within saidoblong aperture in substantially close-fitting relation with the sidesthereof only.

6. In a selector mechanism, signal responsive means, a selector elementpresentable in either of two selective positions under control of saidmeans, a bracket having at one end thereof means for pivotallysupporting said element, said bracket havin a circular aperture at theother end thereof and an elongated aperture intermediate the ends, arotational member having an eccentric portion disposed within saidcircular aperture in substantially close-fitting relation therewith, anda rotational member having an eccentric portion disposed within saidelongated aperture in substantially close-fitting relation with thesides thereof only.

7 In a selector mechanism, a mounting plate, signal responsive meanscarried by said mounting plate, a bracket having clearance aperturescarried by said mounting plate, clamping means extending through saidclearance apertures and threadedly engaging said mounting plate, aselector element pivotally supported by said bracket and presented ineither of two selective positions under control of said signalresponsive means, said bracket having a circular aperture and anelongated aperture therein, a member rotationally supported by saidmounting plate and having a cylindrical eccentric portion disposedwithin said circular aperture in close-fitting engagement therewith, andanother member rotationally supported by said mounting plate and havinga cylindrical portion disposed within said elongated aperture inclose-fitting engagement:

with the sides thereof only. I

8. In a, selector mechanism, a selector element presented in either oftwo selective positions, signal responsive means for controlling thepresen-:

tation of said selector element in said positions, and means forovercoming reactive forces op-' posing the presentation of said elementin said sement at rest condition in said selective positions.

10. In a selector mechanism, a selector element pivotally mounted forpresentation in either of two selective positions, signal controlledmeans for effecting the presentation of said element in said positions,a cylindrical abutment pin carried by said selector element, and apivotally mounted spring biased detent arm having a disc-like portionmaintained in surface engagement with said abutment pin.

11. In a selector mechanism, a selector element pivotally mounted forpresentation in either of two selective positions, signal controlledmeans for effecting the presentation of said element in said positions,an abutment pin carried by said selector element, a pivotally mountedspring biased detent having an open aperture in which said abutment pinis disposed, said aperture having substantially parallel sides formingpositive stops for said selector element, and oppositely sloping camsurfaces at the base thereof for resisting reactive forces postponingthe arrival of said selector element at rest condition in either of saidpositions.

12. In a selector mechanism, a selector element pivotally mounted forpresentation in either of two selective positions, signal controlledmeans for effecting the selective presentation of said element in saidpositions, an abutment pin carried by said selector element, a pivotallymounted and spring biased detent arm having an enclosed aperture inwhich said abutment pin is disposed, said aperture affording positivestops for said selector element, said aperture also afiording an arcuatesurface with which said abutment pin cooperates to expedite restorationof said detent arm to normal position, and said aperture also affordingoppositely sloping cam surfaces with which said abutment pin cooperatesto oppose the active forces tending to postpone the arrival of saidselector element at rest condition in said selective positions.

13. In a selector mechanism, a selector element pivotally mounted forpresentation in either of two selective positions, signalcontrolledmeans for effecting the presentation of said element in saidselective positions, an abutment pin carried by said selector element, apivotally mounted detent arm having an aperture in which said abutmentpin is disposed, meansfor shifting the pivotal axis of said detent arm,and means for clamping said shifting means in any efiective positionthereof.

14. In a selector mechanism, a mounting plate, a bracket adjustablysupported by said plate, a selector element pivotally supported by saidbracket and adapted to be presented in either of two selectivepositions, signal controlled means supported by said plate for efiectingthe presentation of said element in said selective positions, a lockinglug carried by said selector element at a point spaced from the pivotalmounting thereof, a pivotally mounted lock lever cooperating with saidlug to block said selector element in either of its selective positions,a pivotally mounted detent arm cooperating with said selector elementand afiording positive stops therefor, and

means for adjusting the pivotal mounting of said detent arm inaccordance with the adjustment of said bracket.

15. In a selector mechanism, signal responsive means, a selector elementpresented in either of two selective positions under control of saidsignal responsive means, means for pivotally supporting. said selectorelement, means for pivotally supporting said supporting means, andeccentric means for controlling the pivotal position of the lastmentioned means.

16. In cooperation with a selector mechanism including a foundationmember having a circular aperture therein and adjust-ably mountedthereon an element pivotally supporting selector means, a manuallyoperable tool for adjusting said element including a cylindrical portiondimensioned to enter said aperture and be rotationally guided thereby,and another cylindrical portion eccentric to the first mentionedcylindrical portion adapted to engage and effect adjustment of saidselector means supporting element.

EDWIN W. F. HANKE.

